the letters were addressed to president obama, senator rodger wicker and a judge in that state. they are likely sent from a writer who is a frequent writer to federal officials. two letters were quite similar. both letters determined to be similar based on targets, post marks and et cetera. both are postmarked out of memphis, tennessee on april 8, 2013. both letters signed, quote, i am k. c. and i approve this message." at the white house here is jay carney's take. >> there was a letter. the off-site facility feeted a suspicious substance and a test was undertaken. the fbi has the lead this that investigation. >> with lawmakers and law enforcement on edge, multiple senate offices had reports of suspicious mail today, including this phoenix, senator jeff flake from arizona. >> there was no harmful substance on the letter, but the letter with ricin was sent from tennessee to senator wicker. this letter came from tennessee with no return address and with an oily substance on it. so it was troubling, and my staff alerted authorities, as they should have, and it was tested. >> just m